The continuation of the study of the cellular immunity in patients with pernicious anemia and atrophic gastritis by means of the skin- window technique, using the biopsies from the stomach of patients with atrophic gastritis and pernicious anemia and the method of Hoff- Jorgenson, as applied to the study of breast cancer by M. Black and H. Leis from our Institution. The study of the cytotoxic effect upon the parietal cells of the sensitized lymphocytes from patients with pernicious anemia and atrophic gastritis using the method developed by I. Brus and G.B.J. Glass. The study of the titer of the circulating T- lymphocytes in the blood of these patients by the "rosette technique" as used for the same purpose in various blood diseases. The continuation of the studies on the content of intrinsic factor and microsomal parietal cell antigen in the parietal cells of man at various stages of mucosal injury and on the localization of intrinsic factor in the gastric mucosa of various species. The continuation of the studies on the separation of various glycoproteins from human and rat gastric mucosa, their antigenicity and cellular derivation as well as the quantitation of the mucosubstances in the gastric juice by immunological methods. The continuation of the study on the effect of intrinsic factor antibodies and parietal cell antibodies on the experimentally induced gastric cancer of the rat.